Maryland State Insect - Baltimore Checkerspot Butterfly

The Baltimore Checkerspot Butterfly (Euphydryas phaeton) has been the official arthropodic emblem of the State since 1973 (Chapter 253, Acts of 1973; Code State Government Article, sec. 13-301(a)). Although the law that made it the State Insect did not give a reason for the designation, certainly the Butterfly's name endears it to Marylanders.
Baltimore Checkerspot Butterfly. Photo by Mark S. Garland, Audubon Naturalist Society.

Butterflies, like bees, are pollinators of crops and wild flora, and the Baltimore Checkerspot is no exception. Its body or thorax is dark brown, a color which extends to its wings, spotted white and then orange on their edges. As part of the family Nymphalidae (Brush-footed Butterflies), it bears hairy forelegs too short for walking. The prominent knobs on its antennae also are a trait of this butterfly family.

Like other butterflies, the Baltimore Checkerspot searches for one kind of host plant from which it will gain nourishment during its period of growth. In this case, the Turtlehead (Chelone glabra) is the only host plant that this butterfly will use. In wet meadows and ditches, the Baltimore Checkerspot Butterfly seeks out the Turtlehead, a creamy white pink-rimmed flower of the snapdragon family. Here, it lays eggs on the undersides of the plant's leaves. In summer, the eggs hatch into orange and black caterpillars (larvae) which feed off this host plant.

Over a period of a few weeks, each caterpillar, as it grows, will molt or shed its skin several times before reaching its full size. Following the last molt, the pupa or chrysalis appears. Within a flexible shell, the chrysalis is a semiliquid in which the butterfly forms. From it emerges an adult butterfly.